Angel Pons has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/33439 )
Change subject: mb/asrock/h110m: Unselect incorrect Kconfig symbol ......................................................................
Patch Set 1:
Patch Set 1: -Code-Review
AFAIUI, this is writing the value 0x40 to the global register 0x2A, which sets bit7=0 and bit6=1.
For the NCT6776, this selects the COMA function on all the COMA pins.
For the NCT6791, this selects the COMA function on pin 29, and selects the GPIO8 function on pins 30-36.
Guess what happens to serial.
Ok, that does indeed sound wrong, so this patch probably won't break things that aren't already broken. Would probably be good to ping the author of that board port to get things sorted out.
@Maxim Polyakov, any comments?